How to Sign PDFs with Java

<dependency>
    <groupId>com.turbodocx</groupId>
    <artifactId>turbodocx-sdk</artifactId>
    <version>0.1.4</version>
</dependency>

implementation 'com.turbodocx:turbodocx-sdk:0.1.4'

import com.turbodocx.TurboDocxClient;
import com.turbodocx.models.*;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.Arrays;

public class Main {
    public static void main(String[] args) throws Exception {
        // Create client with sender configuration
        TurboDocxClient client = new TurboDocxClient.Builder()
            .apiKey(System.getenv("TURBODOCX_API_KEY"))       // REQUIRED
            .orgId(System.getenv("TURBODOCX_ORG_ID"))         // REQUIRED
            .senderEmail(System.getenv("TURBODOCX_SENDER_EMAIL"))  // REQUIRED
            .senderName(System.getenv("TURBODOCX_SENDER_NAME"))    // Recommended
            .build();

        // Read PDF file
        byte[] pdfFile = Files.readAllBytes(Paths.get("contract.pdf"));

        // Send document for signature
        SendSignatureResponse result = client.turboSign().sendSignature(
            new SendSignatureRequest.Builder()
                .file(pdfFile)
                .fileName("contract.pdf")
                .documentName("Partnership Agreement")
                .recipients(Arrays.asList(
                    new Recipient("John Doe", "john@example.com", 1)
                )))
                .fields(Arrays.asList(
                    new Field.Builder()
                        .type("signature")
                        .recipientEmail("john@example.com")
                        .template(new FieldTemplate.Builder()
                            .anchor("{signature1}")
                            .placement("replace")
                            .size(new FieldSize(100, 30))
                            .build())
                        .build()
                )))
                .build()
        );

        System.out.println("Document ID: " + result.getDocumentId());
    }
}